• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.967-973
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• 2021

In 2011, an earthquake and subsequent tsunami hit the Fukushima Daiichi Nuclear Power Plant, causing simultaneous accidents in several reactors. This accident shows us that if there are several reactors on site, the seismic risk to multiple units is important to consider, in addition to that to single units in isolation. When a seismic event occurs, a seismic-failure correlation exists between the nuclear power plant's structures, systems, and components (SSCs) due to their seismic-response and seismic-capacity correlations. Therefore, it is necessary to evaluate the multi-unit seismic risk by considering the SSCs' seismic-failure-correlation effect. In this study, a methodology is proposed to obtain the seismic-response-correlation coefficient between SSCs to calculate the risk to multi-unit facilities. This coefficient is calculated from a probabilistic multi-unit seismic-response analysis. The seismic-response and seismic-failure-correlation coefficients of the emergency diesel generators installed within the units are successfully derived via the proposed method. In addition, the distribution of the seismic-response-correlation coefficient was observed as a function of the distance between SSCs of various dynamic characteristics. It is demonstrated that the proposed methodology can reasonably derive the seismic-response-correlation coefficient between SSCs, which is the input data for multi-unit seismic probabilistic safety assessment.

• Journal of Distribution Science
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• v.22 no.4
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• pp.59-68
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• 2024

Purpose: The function of internal audit is to help achieve company goals and targets by minimizing the impact of business risks. The distribution of internal audit activities in carrying out control and supervision covers all aspects or activities at all levels of management. The aim of the research is to determine the distribution of risk-based internal audit effectiveness assessments in companies. Data and Research Design Methodology: Researchers examined research trends regarding things that could influence the distribution of the effectiveness of the internal audit function from 2007 to 2023.This research used a systematic literature review (SLR) research method. This research used 23 papers sourced from the Scopus database. Results: The distribution of the effectiveness of audit services provided by internal auditors is more influenced by the personal characteristics of internal auditors and has little to do with the leadership of the chief internal auditor, technology, and risk management. Conclusion: The distribution of monitoring services provided by internal auditors covers all levels of departments or divisions of the organization. The assessment of internal audit effectiveness is more influenced by the auditor's personal attributes such as independence, competence, and management support.

• Journal of Sasang Constitutional Medicine
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• v.25 no.3
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• pp.180-194
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• 2013

Objectives Impaired lung function(ILF) and sasang constitution(SC) is associated with metabolic syndrome(MS). However, the relationship between ILF and SC is unclear. So, we assessed the relationship between ILF and MS according to SC, and examined whether SC is an independent risk factor for ILF. Methods This study included 1,148 subjects 40years and older who were performed the health examination at Kyung Hee University Hospital in Korea between December 2011 and February 2013. We defined ILF if FVC or $FEV_1$ value were less than lower limit of normal(LLN), and classified ventilatory patterns as obstructive pattern and restrictive pattern. MS was assessed according to AHA/NHLBI criteria. We used multivariate logistic regression to analyze the association of ILF with MS respective to SC types, and to identify the risk of SC types for ILF. Odds ratio(OR) was calculated by adjusting for age, sex, smoking status, drinking, physical activity, and BMI. Results In whole subjects, ILF was associated with MS [OR (95% CI), 1.69 (1.24-2.31) for FVC, 1.67 (1.20-2.33) for $FEV_1$]. And in Taeeum type(TE type) and Soeum type(SE type), ILF was associated with MS [1.63 (1.10-2.42) for FVC, 1.48 (1.01-2.24) for $FEV_1$ in TE type; 6.93 (1.14-42.00) for FVC in SE type], while in Soyang type(SY type), it wasn't. The restrictive pattern was associated with MS in TE type and SE type, while in SY type, it wasn't. Furthermore, TE type and SY type had more risk for ILF than SE type [1.71 (1.12-2.59) for SY type, 1.95 (1.23-3.08) for TE type in FVC; 2.06 (1.26-3.36) for TE type in $FEV_1$; 1.85 (1.21-2.85) for SY type, 2.17 (1.35-3.49) for TE type in Restrictive pattern]. Conclusions These results show that SC is an independent risk factor for ILF, especially TE type and SY type than SE type, and the prevalence of MS is an independent risk factor for ILF in TE type.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.76-84
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• 2021

The quality assurance activities can detect the factors that affect the quality based on risk identification in the course of mass production. Risk identification is conducted with risk analysis, and the risk analysis method for the rotorcraft landing system is selected by failure mode effects analysis (FMEA). FMEA is a method that detects the factors that can affect the product quality by combining severity, occurrence, and detectability. The results of FMEA were prioritized using the risk priority number. On the other hand, these methods have certain shortcomings because the severity, occurrence, detectability are weighted equally. Dempster-Shafer evidence theory can conduct uncertainty analysis for the opinions with personal reflections and subjectivity. Based on the theory, the belief function and the plausibility function can be formed. Moreover, the functions can be utilized to evaluate the belief rate and credibility. The system is exposed to impact during take-off and landing. Therefore, experts should manage failure modes in the course of mass production. In this paper, FMEA based on the Dempster-Shafer evidence theory is discussed to perform risk analysis regarding the failure mode of the rotorcraft landing system. The failure priority was evaluated depending on the factor values. The results were derived using belief and plausibility function graphs.

• Journal of Radiation Protection and Research
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• v.42 no.2
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• pp.130-140
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• 2017

Background: With the need for a domestic level 3 probabilistic safety assessment (PSA), it is essential to develop a Korea-specific code. Health effect assessments study radiation-induced impacts; in particular, long-term health effects are evaluated in terms of cancer risk. The objective of this study was to analyze the latest cancer risk models developed by foreign organizations and to compare the methodology of how they were developed. This paper also provides suggestions regarding the development of Korean cancer risk models. Materials and Methods: A review of cancer risk models was carried out targeting the latest models: the NUREG model (1993), the BEIR VII model (2006), the UNSCEAR model (2006), the ICRP 103 model (2007), and the U.S. EPA model (2011). The methodology of how each model was developed is explained, and the cancer sites, dose and dose rate effectiveness factor (DDREF) and mathematical models are also described in the sections presenting differences among the models. Results and Discussion: The NUREG model was developed by assuming that the risk was proportional to the risk coefficient and dose, while the BEIR VII, UNSCEAR, ICRP, and U.S. EPA models were derived from epidemiological data, principally from Japanese atomic bomb survivors. The risk coefficient does not consider individual characteristics, as the values were calculated in terms of population-averaged cancer risk per unit dose. However, the models derived by epidemiological data are a function of sex, exposure age, and attained age of the exposed individual. Moreover, the methodologies can be used to apply the latest epidemiological data. Therefore, methodologies using epidemiological data should be considered first for developing a Korean cancer risk model, and the cancer sites and DDREF should also be determined based on Korea-specific studies.

• Journal of Preventive Medicine and Public Health
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• v.39 no.4
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• pp.359-364
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• 2006

Objectives: The object of this study is to assess the relationship between socioeconomic factors and the predicted 10-year risk of cardiovascular disease by using health risk appraisal of ischemic heart disease. Methods: The study population was taken from The 2001 Korea National Health and Nutrition Survey, and it consisted of 1,566 men and 1,984 women aged 30-59. We calculated 10-year risk using the risk function of ischemic heart disease as developed by Jee. The educational level and equivalized household income were dichotomized by a 12 years education period and the median income level. Occupation was dichotomized into manual/non-manual work. We stratified the population by age(10 years) and sex, and then we rated the risk differences according to socioeconomic factors by performing t-tests for each strata. Results: There were gradients of the predicted 10-year risk of ischemic heart disease with the educational level and the equivalized household income, and thet was an increasing tendency of risk differences with age. Manual workers didn't show significant risk difference from non-manual workers. Conclusions: There was definite relationship between low socioeconomic position and the predicted risk of ischemic heart disease in the future.

• Journal of Navigation and Port Research
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• v.36 no.4
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• pp.321-327
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• 2012

Logistics in a supply chain network has become an important operational strategy in a competitive market. A number of internal and external risks involved in the logistics operations in a company tend to create problems in fulfilling customer orders. This research presents how ERM (enterprise risk management) can be used to identify, assess, and control logistics risks. An electronic company's logistics activities were used as an industry case to demonstrate a way to identify and assess risks surrounding global logistics function. This paper has further presented action plans to mitigate the impact of the risks that occur.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.4
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• pp.213-220
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• 2017

This study examines the limitations of existing crime mapping that relies mainly on reported crime data, suggests a crime mapping method based on experts' and users' assessments of a neighborhood environment as an alternative approach, and conducts a case study on a real-world site by applying the suggested approach. According to the results of the case analysis, while the areas adjoining arterial roads with heavy pedestrian traffic were shown as high crime risk areas in the crime map based on actual reported crime data, the areas adjoining local roads with low pedestrian traffic were high-risk areas in the crime risk area map based on experts' and residents' evaluations. This study makes a contribution to the field in that it demonstrates the detailed application process of crime risk area mapping according experts' and residents' evaluations, compares the results with those of an existing crime map, and finally shows that the former can function as a complement to the latter.

• Neonatal Medicine
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• v.25 no.3
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• pp.91-95
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• 2018

Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) is increasingly being recognized as a cause of morbidity and mortality in preterm infants. Recently, BPD-PH has also been shown to have additional long-term negative effects on neurodevelopmental outcomes and right ventricular function. Several significant risk factors associated with the development of BPD-PH have been identified. A screening strategy for BPD-PH is needed for infants presenting more than one risk factor. In addition, an early echocardiogram within 14 days of age may be a useful tool to identify infants at high-risk for BPD-PH. We have reviewed recent progress in research concerning clinical characteristics, presentation, and outcomes of BPD-PH and have suggested direction for future studies.

• Wind and Structures
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• v.13 no.2
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• pp.95-108
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• 2010

This review paper discusses research from the last few years relating to windborne debris risk models and the essential elements of engineering damage prediction models. Generic types of windborne debris are discussed. The results of studies of debris trajectories that are relevant to damage models are described - in particular the horizontal component of debris velocity as a function of distance travelled. The merits of impact momentum versus impact kinetic energy as a relevant parameter for predicting damage are considered, and how published data from generic cannon Impact tests can be used in risk models. The quantitative variation of debris impact damage with wind speed is also discussed. Finally the main elements of previously-proposed debris damage models are described.